While the video won't air until Thursday, the band's Red Nose Day single was released on Sunday. One Way or Another (Teenage Kicks) is a mash-up of Blondie's 1979 hit and the Undertones' 1978 classic, which was a favourite of John Peel.
On Sunday, Cameron tweeted a photograph of himself and One Direction, standing outside No 10. "Enjoyed my cameo in @onedirection's vid for @comicrelief charity single," he wrote. "Glad to help with the filming location." In another message , Cameron wished them "good luck" and confirmed that a government donation to Comic Relief will cancel out all VAT paid on the single.
In addition to filming parts of the video at Downing Street, One Direction shot scenes in Japan and Ghana during their recent world tour. "Today was the most amazing day I've had so far … in my life ever," Harry Styles said after the band's visit to Accra. "When you're there and you get the smells, your eyes hurt from the smoke, you cough, you're feeling it all." But not everyone was happy with the way One Direction focused on the country's deprived areas. "Next [time] you visit a country, remember like yours there are beautiful and ugly parts," wrote Ghanaian actor Lydia Forson.
Although this is Cameron's first documented case of One Direction infection, he is by no means a newcomer to Comic Relief. He participated in 2011's comedy broadcast, as well as in last year's Sport Relief run. Tony Blair and Gordon Brown have also made appearances; Brown even made a fool of himself beside JLS.
Meanwhile, the PM and One Direction could have another meet-up at this month's NME awards. Cameron and Styles have been nominated as villains of the year.
guardian.co.uk © Guardian News and Media Limited 2010
image: © Foreign and Commonwealth Office